When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Best to compare gross numbers, 650/650 to 800/800 (with headers). I have paid this much and gotten less from others. And it is from Katech. And includes additional cooling.
Best to compare gross numbers, 650/650 to 800/800 (with headers). I have paid this much and gotten less from others. And it is from Katech. And includes additional cooling.
Looks like a dependable kick *** build that can be driven daily, No meth correct?
Can you also make the dyno sheet not show losing 75hp from 5500 RPM to 6500 LOL!
all kidding aside, why does it fall down so hard after 5500. Looks like something ain't quite right.
Just asking what is the choke from?
is it a fuel issue?
I don't think you're reading it right. Torque falls off as you'd expect and hp stays about the same or climbs a little bit in that window. I think you were looking at torque and thinking horsepower perhaps?
I don't think you're reading it right. Torque falls off as you'd expect and hp stays about the same or climbs a little bit in that window. I think you were looking at torque and thinking horsepower perhaps?
Umm..No!
The red pulls are the modded pulls..Blue is old/stock.
The "RED" HP falls from 5500 - 6500 pretty dramatic.
I'm sure most guys would love the explosive TQ, but I'm still wondering why the significant drop. I'm sure tuner can explain as they seem quite qualified.
The thick Red line is what Im talking about... at 4500 Rpm the motor is making just shy of 580 HP, increases to a max of 652HP at only 5500RPM. Then by 6400 RPM the motor has decreased in power to approximately 580HP.
Simple math 652-580=72 Sorry for my original sentence of 75HP.
Simple math and simple graph.
The amount of TQ was not my point, my question to be more specific was why does the motor lose power so rapidly after 5500. I think you can say the motor hits a brick wall at 6000...PERIOD!
The factory redline of the LT4 is 6500 and rightly so as you see on the Blue HP line that power is at 500HP at 5500, then "drifts" up 20HP by 6000 RPM then "drifts" down 20 to 6500 RPM. Hence, the 6500 RPM redline.
I think you can pick up that my first comment was a joke, then I simply asked why the drop. Jason will know!
My thoughts are fuel or probably the OE cam is too small for the increased airflow. I'm curious for the tuner's response as he is the brain behind the build.
I'm also curious if the rev limiter is lowered in the final tune is the power curve is lower in the RPM range (not to be confused with less over all HP and TQ)?
The thick Red line is what Im talking about... at 4500 Rpm the motor is making just shy of 580 HP, increases to a max of 652HP at only 5500RPM. Then by 6400 RPM the motor has decreased in power to approximately 580HP.
Simple math 652-580=72 Sorry for my original sentence of 75HP.
Simple math and simple graph.
The amount of TQ was not my point, my question to be more specific was why does the motor lose power so rapidly after 5500. I think you can say the motor hits a brick wall at 6000...PERIOD!
The factory redline of the LT4 is 6500 and rightly so as you see on the Blue HP line that power is at 500HP at 5500, then "drifts" up 20HP by 6000 RPM then "drifts" down 20 to 6500 RPM. Hence, the 6500 RPM redline.
I think you can pick up that my first comment was a joke, then I simply asked why the drop. Jason will know!
My thoughts are fuel or probably the OE cam is too small for the increased airflow. I'm curious for the tuner's response as he is the brain behind the build.
I'm also curious if the rev limiter is lowered in the final tune is the power curve is lower in the RPM range (not to be confused with less over all HP and TQ)?
I suppose I could plug this dyno curve into a simulator, but I might as well just ask:
It makes massive torque, but that torque does fall off with RPM quite a bit (as RandyN notes). Would it make sense to short-shift this car around 5500 or would it still be faster to hold the shift to 6500 I wonder?
I suppose I could plug this dyno curve into a simulator, but I might as well just ask:
It makes massive torque, but that torque does fall off with RPM quite a bit (as RandyN notes). Would it make sense to short-shift this car around 5500 or would it still be faster to hold the shift to 6500 I wonder?
Still faster to shift at 6500.
Guys, keep in mind what we're talking about here. Torque "falling off" from the tire-shredding 730rwtq at 3400rpm? The car is scary fast. I never think "oh man the torque is really falling off". LOL.
speaking of TQ, your customer's car has almost 150lbs more than the stock car at peak, but at 6500 only 60 more. I would bet your customers car will run a quicker e.t shifting at 6000.
Especially a 8sp auto, but who cares. I just wanted know why the drop at 5500 and I think you answered.
thx
When you're talking about horsepower at a particular RPM, you are talking about TQ. The dropoff in HP you referred to is because of the dropoff in TQ over the specified RPM range. I was just giving you the benefit of the doubt. It's all the same thing - having both on the graph is just a matter of convenience, you only need TQ. HP is calculated, not measured.
05-09-2017, 03:23 PM
Katech Stage 3 C7 Z06 SN# 05
The car is scary fast. I never think "oh man the torque is really falling off". LOL.